remove db67 from coredb,decom db64,db65,db66,db70

- remove db67 from role/coredb config
- remove db67 from site.pp
- remove db64,db65,db66,db67,db70 from DHCP

ok to remove this researchdb?

RT #7129

Change-Id: I2b6bf8555b0f3af120272e7dfb36f8b7e39aa23f